Office for Nuclear Regulation

To conduct LC24 and LC27 compliance inspections at the Fuel Handling facility on the Sellafield Ltd site at Sellafield, Cumbria

Executive summary

Purpose of intervention

This intervention was undertaken on 20 and 21 May 2015 in the Fuel Handling Facility (FHP) on Sellafield Limited’s nuclear licensed site at Sellafield, Cumbria.

Inspection of Licence Condition (LC) compliance at nuclear licensed sites forms a significant part of ONR’s activities.  ONR’s Sellafield Programme has defined a programme of system inspections and LC compliance inspections to be undertaken on the Sellafield site, this is a key aspect of ONR’s regulatory strategy (for the Sellafield site).  Undertaking this intervention is consistent with this strategy, and is identified on ONR’s PP4 inspection plan which covers Sellafield Limited’s Magnox Operating Unit This facility, operated by the licensee Sellafield Ltd (SL), is considered to be an appropriate target for an intervention because foreseeable events on this plant could result in a significant offsite release.

Interventions Carried Out by ONR

LC24 ‘Operating instructions’ requires the licensee to ensure that all operations which may affect safety are carried out in accordance with written instructions (Operating Instructions [OIs]), and that such OIs include any instructions necessary in the interests of safety and any instructions necessary to ensure that any OIs are implemented.

LC27 ‘Safety mechanisms, devices and circuits’ requires the licensee to ensure that plant is not used unless the necessary Safety Mechanisms, Devices and Circuits (SMDCs) are installed and functioning. SMDCs must deliver their role in preventing or mitigating a radiological consequence.

I completed the compliance inspections; which comprised office based discussions and plant walk downs, against LC24 and LC27 in accordance with the following ONR guidance:

Explanation of Judgement if Safety System Not Judged to be Adequate

N/A.  This was not a safety system inspection.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

During my inspection of LC 24 compliance, I sampled a number of required OIs (rOIs) which specify limits and conditions derived from the safety case associated with the requirement for container nitrogen ullaging and which specified the success criteria for ullaging.  It was my opinion that the rOIs themselves are clear and unambiguous. I also examined the OIs for ullaging containers and confirmed that they were adequate as were the associated quality plans; the licensee’s means of demonstrating compliance with the rOIs.  I examined a number of Maintenance Instructions (MI) for ullaging, pond water temperature monitoring and pond water level detection system and found these to be clear and unambiguous. Additionally, I confirmed the MIs did specify robust tests to confirm the equipment in question did meet its safety function.  Based on my sample, I consider the licensee met the requirements of LC24, and therefore judge an IIS rating of 3 (adequate) to be appropriate.  I identified no areas requiring improvements.

During my inspection of LC 27 compliance, I sampled a range of SMDCs for ullaging, pond water temperature monitoring and pond water level detection systems.  In each case, I established the safety function (from the safety case), examined the Plant Maintenance Schedule (PMS) to confirm the necessary maintenance and testing was prompted, the scope of work was detailed, and the periodicity was appropriate.  I confirmed from the PMS that maintenance and testing had been undertaken at the appropriate frequency, and that there was no overdue maintenance or testing activities at the time of my inspection.  During a plant walk down I was able to examine much of my chosen sample, and confirmed it appeared to be in good working order.   Based on my sample, I consider the licensee to meet the requirements of ONR’s guidance for LC27, and therefore judge an IIS rating of 3 (adequate) to be appropriate.  I identified no areas that required improvement.

Conclusion of Intervention

No issues were raised as a result of this intervention.  Based on the evidence gathered, no significant matters have been identified that are likely to impact on nuclear safety on the Sellafield site at this time.